Inhalator for administering powder composition

ABSTRACT

An inhalator including an inhalator body including a powder receiving chamber for receiving a powder, an air-powder mixture reservoir for temporarily storing an air-powder mixture flowing from the powder receiving chamber, and a diluent air passage for introducing a diluent air into the air-powder mixture reservoir. The air-powder mixture is formed within the powder receiving chamber when an air is introduced into the powder receiving chamber. The air-powder mixture within the air-powder mixture reservoir is admixed with a diluent air introduced thereinto through the diluent air passage. The diluted air-powder mixture is discharged from an air-powder mixture outlet into a user&#39;s oral or nasal cavity. A powder composition for inhalators includes at least two kinds of fine particles different in particle diameter.

BACKGROUND OF THE INVENTION

The present invention relates to an inhalator suitable for administeringa powder or powder composition, and a powder composition containingpowders different in particle diameter from each other and a process foradministering the powder composition using inhalators.

Generally, a powder inhalator is used for inhaling a powder or powdercomposition such as a powdered medicine into a human body through theoral or nasal cavity. The inhalator includes an inhalator body having anair intake path for introducing an ambient air and a suction openingthrough which an air-powder mixture within the inhalator body is suckedinto the oral or nasal cavity. A powder receiving chamber for receivingthe powder is disposed within the inhalator body and communicated withthe outside of the inhalator body via the air intake path. An air-powdermixture path extends from the powder receiving chamber to the suctionopening. The air-powder mixture is formed when the air is introducedinto the powder receiving chamber through the air intake path. Theair-powder mixture is then transmitted from the powder receiving chamberto the suction opening via the air-powder mixture path.

There are several types of powders different in aerodynamic meanparticle diameter as follows: a powder having the aerodynamic meanparticle diameter of not less than 7 μm and depositing in an oral cavityor hypoglottis, a powder having the aerodynamic mean particle diameterof 5-7 μm and depositing in a throat, a powder having the aerodynamicmean particle diameter of 3-5 μm and depositing in a trachea, a powderhaving the aerodynamic mean particle diameter of 1-3 μm and depositingin bronchi, and a powder having the aerodynamic mean particle diameterof not more than 1 μm and depositing into alveoli, and the like. Thepowder having the aerodynamic mean particle diameter of not more than 3μm is required to surely reach affected areas of the human body. Also,the powder such as an acrid powder is preferably dosed in several partsupon being inhaled.

In addition, there has been proposed powder tobacco for use with theinhalator. The powder tobacco can be substituted for a usual smokingtobacco because the powder tobacco provides a smoking feeling upon beinginhaled. When the powder tobacco is used, one dose of the powder tobaccois dispensed in parts from the inhalator upon each inhalation.

The human bronchi and alveoli exist in deeper portions of the humanbody. Therefore, in order to ensure stable deposit of the powder havingthe particle diameter of not more than 3 μm in the bronchi and alveoli,it is preferable to dose the powder in parts, i.e., dispense a smallamount of the powder each inhalation.

However, in the earlier technique, the whole amount of the powderreceived within the powder receiving chamber of the inhalator isdispensed from the inhalator by the inhalation substantially at onetime. If a dose of the powder having the particle diameter of not morethan 3 μm is inhaled through the inhalator upon inhalation, a largeamount of the powder dosed will be deposited in the oral cavity ortrachea before being deposited in the bronchi and alveoli.

Further, there is known a process for administering a particulatemedicament having a specific mean particle diameter into a patient'slungs upon the patient breathing. International Publication No.WO97/36574 discloses a process and device for inhalation of particulatemedicament. The process includes (i) providing an inhalator whichcontains at least one dose of medicament particles comprising sphericalhollow particulates of respirable particle size suitable for depositionin a human lungs, and (ii) removing the spherical hollow particulatesfrom the inhalator. In the earlier technique, the particulate medicamenthaving the specific particle diameter is used with the inhalator, butthere is not described inhalation on multi-purpose prescription, forinstance, one-time inhalation of multiple particulate medicaments forthe purpose of simultaneous deposition in different portions such as thetrachea and the alveoli of the patient's body. In order to follow themulti-purpose prescription, it is required that the patient repeatedlyinhales separate doses of particulate medicaments for differentprescriptions, takes a specific particulate medicament formulated forthe multi-purpose prescription, or is treated with the combination ofvarious prescriptions including peroral medicament, injection,application of fomentation, and the like.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an inhalator capableof dispensing one dose of a powder or powder composition in partstherefrom.

It is another object of the present invention to provide a powdercomposition containing powders different in particle diameter from eachother and a process for administering the powder composition usinginhalators, which are suitable for simultaneous deposition in differentportions of the human body by one-time inhalation.

According to one aspect of the present invention, there is provided aninhalator for administering an air-powder mixture, comprising:

an inhalator body including an air intake path for introducing air intothe inhalator body, and an air-powder mixture outlet for discharging theair-powder mixture from the inhalator body;

a powder receiving chamber adapted to receive a powder, the powderreceiving chamber being disposed within the inhalator body andcommunicated with an outside of the inhalator body through the airintake path;

an air-powder mixture path adapted to transmit the air-powder mixtureflowing from the powder receiving chamber to the air-powder mixtureoutlet;

an air-powder mixture reservoir adapted to temporarily store theair-powder mixture flowing from the powder receiving chamber, theair-powder mixture reservoir being disposed within the air-powdermixture path; and

a diluent air passage adapted to introduce a diluent air into theair-powder mixture reservoir, the diluent air passage communicating theair-powder mixture reservoir with the outside of the inhalator body.

According to a further aspect of the present invention, there isprovided an inhalator for administering an air-powder mixture,comprising:

a casing including an air intake inlet for introducing air into thecasing, and an air-powder mixture outlet for discharging the air-powdermixture from the casing;

powder receiving means for receiving a powder within the casing andpermitting the powder to be admixed with the air introduced from the airintake inlet;

air-powder mixture storing means for temporarily storing the air-powdermixture passing through the powder receiving means;

diluent air passage means for permitting a diluent air to flow into theair-powder mixture storing means; and

air-powder mixture path means for permitting the air-powder mixture toflow from the powder receiving means to the air-powder mixture outletvia the air-powder mixture storing means.

According to another aspect of the present invention, there is provideda powder composition for use with an inhalator, comprising:

at least two kinds of fine particles selected from a first kind of fineparticles having an aerodynamic mean particle diameter of not less than7 μm, a second kind of fine particles having an aerodynamic meanparticle diameter of 5-7 μm, a third kind of fine particles having anaerodynamic mean particle diameter of 3-5 μm, a fourth kind of fineparticles having an aerodynamic mean particle diameter of 1-3 μm, and afifth kind of fine particles having an aerodynamic mean particlediameter of not more than 1 μm.

According to a further aspect of the present invention, there isprovided a process for administering a powder composition using aninhalator, comprising:

preparing the powder composition containing at least two kinds of fineparticles selected from a first kind of fine particles having anaerodynamic mean particle diameter of not less than 7 μm, a second kindof fine particles having an aerodynamic mean particle diameter of 5-7μm, a third kind of fine particles having an aerodynamic mean particlediameter of 3-5 μm, a fourth kind of fine particles having anaerodynamic mean particle diameter of 1-3 μm, and a fifth kind of fineparticles having an aerodynamic mean particle diameter of not more than1 μm;

supplying the powder composition to the inhalator; and

discharging the powder composition from the inhalator.

The other objects and features of this invention will become understoodfrom the following description with reference to the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation of an inhalator of a preferred embodiment,according to the present invention;

FIG. 2 is a longitudinal section of the inhalator, taken along the line2—2 of FIG. 1, showing a rest position of the inhalator;

FIG. 3 is an enlarged section of the inhalator, taken along the line 3—3of FIG. 2;

FIG. 4 is an enlarged section of the inhalator, taken along the line 4—4of FIG. 2;

FIG. 5 is an enlarged section of the inhalator, taken along the line 5—5of FIG. 2; and

FIG. 6 is a view similar to FIG. 2, but showing a use position of theinhalator.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1-6, an inhalator, according to the presentinvention, of a preferred embodiment is explained.

As illustrated in FIG. 1, the inhalator includes an inhalator body 1 asa casing which is formed into a cylindrical shape. Inhalator body 1 ismade of a suitable resin material such as polypropylene, polystyrene,ABS resin and the like. Inhalator body 1 is constituted of cap 3,suction body 4 and capsule body 2 interposed between cap 3 and suctionbody 4. Cap 3 has air intake inlet 7A shown in FIG. 2, through which anambient air is introduced into cap 3 and flows toward capsule body 2 andsuction body 4 as explained later. Cap 3 has a length shorter than thatof capsule body 2 and is rotatably connected with an upstream side ofcapsule body 2. Suction body 4 has air-powder mixture outlet 18 shown inFIG. 2, from which an air-powder mixture formed in inhalator body 1 isdischarged into a user's oral cavity. Suction body 4 has a length longerthan that of capsule body 2 and is rotatably connected with a downstreamside of capsule body 2.

As illustrated in FIG. 2, capsule body 2 has engaging projection 2A andengaging groove 2A1 on the upstream end portion. Engaging projection 2Aand engaging groove 2A1 axially adjacent thereto are engaged withengaging tube portion 3A and engaging projection 3A1 of cap 3,respectively. Capsule body 2 is coupled with cap 3 by the engagement ofengaging projection 2A and engaging groove 2A1 with engaging tubeportion 3A and engaging projection 3A1, respectively. Capsule body 2also has at the downstream end portion, engaging projection 2B andengaging groove 2B1 axially adjacent thereto. Engaging projection 2B andengaging groove 2B1 are engaged with engaging tube portion 4A andengaging projection 4A1 of suction body 4, respectively. Capsule body 2is coupled with suction body 4 by the engagement of engaging projection2B and engaging groove 2B1 with engaging tube portion 4A and engagingprojection 4A1, respectively.

Cocoon-shaped powder receiving chamber 5 is substantially coaxiallydisposed within capsule body 2. Powder receiving chamber 5 is providedfor receiving a dose of a powder or powder composition such asparticulate medicament, powder tobacco or the like. Powder receivingchamber 5 is in communication with the outside of inhalator body 1through air intake path 6, when the inhalator is in a use position asexplained later by referring to FIG. 6. The air-powder mixture is formedwithin powder receiving chamber 5 when the air flows into powderreceiving chamber 5 via air intake path 6 in the use position of theinhalator.

Air intake path 6 is provided for introducing the air into powderreceiving chamber 5. Air intake path 6 includes upstream intake passage7 formed in cap 3 and downstream intake passage 8 formed in capsule body2. Upstream intake passage 7 has an upstream end opening as air intakeinlet 7A which is open to a generally central portion of an axial endface of cap 3. Upstream intake passage 7 has a downstream end openingthat is open to a bottom of engaging tube portion 3A which mates with anaxial end face of engaging projection 2A, in an offset position relativeto the center axis of cap 3. Downstream intake passage 8 has an upstreamend opening that is open to the axial end face of engaging projection 2Ain an offset position relative to the center axis of capsule body 2.Downstream intake passage 8 has a downstream end opening that is open toan upstream end portion of powder receiving chamber 5 and insubstantially alignment with the center axis of capsule body 2.

Capsule body 2 and cap 3 are relatively rotatable to be placed in anon-communication position shown in FIG. 2 and a communication positionshown in FIG. 6. In the non-communication position, the downstream endopening of upstream intake passage 7 and the upstream end opening ofdownstream intake passage 8 are out of alignment with each other. Fluidcommunication between upstream intake passage 7 and downstream intakepassage 8 is blocked so that powder receiving chamber 5 is preventedfrom being fluidly communicated with the outside of the inhalator. Onthe other hand, in the communication position, the downstream endopening of upstream intake passage 7 and the upstream end opening ofdownstream intake passage 8 are in fluid communication with each other.The fluid communication between upstream intake passage 7 and downstreamintake passage 8 is established so that powder receiving chamber 5 isfluidly communicated with the outside of the inhalator. The opening areaat the connection of upstream intake passage 7 and downstream intakepassage 8 may be desirably regulated by adjusting the alignment ofintake passages 7 and 8 to thereby control a flow amount of the airintroduced into powder receiving chamber 5 and therefore control anamount of the powder in the air-powder mixture flowing from powderreceiving chamber 5 toward air-powder mixture outlet 18.

Air-powder mixture path 9 extends between powder receiving chamber 5 andair-powder mixture outlet 18. Air-powder mixture path 9 permits theair-powder mixture to flow from powder receiving chamber 5 to air-powdermixture outlet 18 when the inhalator is in the use position.

First air-powder mixture reservoir 12 is disposed within air-powdermixture path 9. Air-powder mixture reservoir 12 is disposed insubstantially coaxial with suction body 4. Air-powder mixture reservoir12 is adapted to be communicated with powder receiving chamber 5 throughdischarge passage 10 and connecting passage 11 of air-powder mixturepath 9. Air-powder mixture reservoir 12 has a cocoon shape having avolumetric capacity greater than a volumetric capacity of connectingpassage 11. Air-powder mixture reservoir 12 having the greatervolumetric capacity allows the air-powder mixture flowing thereintothrough connecting passage 11 to be temporarily stored.

Discharge passage 10 is formed in capsule body 2 so as to be open topowder receiving chamber 5 at the upstream end and to engagingprojection 2B at the downstream end. An upstream end opening ofdischarge passage 10 is open to a downstream end portion of powderreceiving chamber 5 and in substantially alignment with the center axisof capsule body 2. A downstream end opening of discharge passage 10 isopen to an axial end face of engaging projection 2B in an offsetposition relative to the center axis of capsule body 2. Connectingpassage 11 is formed in suction body 4 so as to be open to engaging tubeportion 4A at the upstream end and to air-powder mixture reservoir 12 atthe downstream end. An upstream end opening of connecting passage 11 isopen to a bottom of engaging tube portion 4A which mates with the axialend face of engaging projection 2B, in an offset position relative tothe center axis of suction body 4. A downstream end opening ofconnecting passage 11 is open to an upstream end portion of air-powdermixture reservoir 12 and in substantially alignment with the center axisof suction body 4. Capsule body 2 and suction body 4 are relativelyrotatable so as to be placed in a non-communication position shown inFIG. 2 and a communication position shown in FIG. 6. In thenon-communication position, the downstream end opening of dischargepassage 10 and the upstream end opening of connecting passage 11 are outof alignment with each other so that fluid communication betweendischarge passage 10 and connecting passage 11 is blocked. Powderreceiving chamber 5 is prevented from being fluidly communicated withair-powder mixture reservoir 12. On the contrary, in the communicationposition, the downstream end opening of discharge passage 10 and theupstream end opening of connecting passage 11 are in fluid communicationwith each other. The fluid communication between discharge passage 10and connecting passage 11 is established so that powder receivingchamber 5 is fluidly communicated with the air-powder mixture reservoir12. The opening area at the connection of discharge passage 10 andconnecting passage 11 may be desirably regulated by adjusting thealignment of discharge passage 10 and connecting passage 11 to therebycontrol an amount of the air-powder mixture flowing from powderreceiving chamber 5 into air-powder mixture reservoir 12.

First diluent air passage 19 is formed in suction body 4 andcommunicated with air-powder mixture reservoir 12. Diluent air passage19 introduces a diluent air into air-powder mixture reservoir 12 whenthe air-powder mixture flows from powder receiving chamber 5 intoair-powder mixture reservoir 12. The diluent air introduced is merged inthe air-powder mixture within air-powder mixture reservoir 12 to therebydilute the air-powder mixture. The diluted air-powder mixture flowingfrom air-powder mixture reservoir 12 has a reduced flow rate and adecreased mixing ratio of the powder relative to the air which arepresent in the diluted air-powder mixture. Diluent air passage 19 isconstituted of four passages arranged in crossed manner in lateralsection in this embodiment as shown in FIG. 3. As illustrated in FIG. 3,each of four diluent air passages 19 has an inlet open to an outercircumferential surface of suction body 4 and an outlet open to acircumferential surface of air-powder mixture reservoir 12.

Second air-powder mixture reservoir 14 is disposed within air-powdermixture path 9 downstream of first air-powder mixture reservoir 12.Air-powder mixture reservoir 14 is disposed in substantially coaxialrelation to suction body 4. Air-powder mixture reservoir 14 iscommunicated with air-powder mixture reservoir 12 through communicationpassage 13 of connecting passage 11 which extends in the axial directionof suction body 4. Air-powder mixture reservoir 14 has a bell shapehaving a volumetric capacity greater than a volumetric capacity ofcommunication passage 13 when viewed in axial cross-section. Air-powdermixture reservoir 14 with the greater volumetric capacity allows theair-powder mixture flowing thereinto through communication passage 13 tobe temporarily stored.

Dispersion part 15 is disposed within air-powder mixture path 9downstream of second air-powder mixture reservoir 14. Dispersion part 15is adapted to prevent the powder in the air-powder mixture flowing fromsecond air-powder mixture reservoir 14 from aggregating together andintimately mix the powder and the air to form a uniform air-powdermixture. Dispersion part 15 includes dispersion chamber 17 and aplurality of dispersion passages 16 connected with dispersion chamber17. Dispersion passages 16, four passages in this embodiment, connectdispersion chamber 17 with air-powder mixture reservoir 14. Each ofdispersion passages 16 has an inlet open to air-powder mixture reservoir14 and an outlet open to dispersion chamber 17. Specifically, dispersionpassage 16 includes an inlet passage portion extending from an outerperipheral portion of air-powder mixture reservoir 14 in the axialdirection of suction body 4. Dispersion passage 16 also includes outletpassage portion 16A that radially inwardly extends from a downstreamside of the inlet passage portion and is open to an upstream end portionof dispersion chamber 17. As illustrated in FIG. 4, dispersion chamber17 has a generally circular-shaped section and outlet passage portion16A extends in a tangential direction of dispersion chamber 17. Theair-powder mixture flowing into dispersion chamber 17 through dispersionpassages 16 forms a swirl flow within dispersion chamber 17. The swirlflow of the air-powder mixture prevents the powder in the air-powdermixture from forming an aggregated mass of the powder.

Second diluent air passage 20 is formed within suction body 4 incommunication with dispersion chamber 17. As seen from FIGS. 2 and 5,four diluent air passages 20 radially extend from grooved portion 4B onan outer surface of suction body 4 to dispersion chamber 17. Groovedportion 4B extends along the entire circumference of the outer surfaceof suction body 4. Diluent air passages 20 introduce the ambient air asa diluent air into dispersion chamber 17 when the air-powder mixturewithin dispersion chamber 17 is directed toward outlet 18 by the user'ssuction.

Regulator 21 for variably controlling a flow amount of the diluent airintroduced into dispersion chamber 17 via diluent air passages 20 isaxially moveably disposed on grooved portion 4B of suction body 4.Regulator 21 is in the form of a ring in this embodiment. Regulator 21has four regulator holes 21A coming into alignment with diluent airpassages 20 by the axial movement of the regulator 21. Regulator 21variably regulates an opening area of each of diluent air passages 20 tothereby variably control the flow amount of the diluent air which ismerged in the air-powder mixture within dispersion chamber 17.

The air-powder mixture passing through dispersion passages 16 anddispersion chamber 17 flows to air-powder mixture outlet 18 from whichthe air-powder mixture is dispensed into the user's oral cavity.Air-powder mixture outlet 18 is communicated with dispersion chamber 17and open to one axial end surface of suction body 4. Air-powder mixtureoutlet 18 is disposed substantially coaxially with the center axis ofsuction body 4.

Referring back to FIG. 1, counter or registration marks 22, 22, 22 areformed on the upstream and downstream end portions of the outercircumferential surface of capsule body 2, downstream engaging tubeportion 3A of cap 3, and upstream engaging tube portion 4A of suctionbody 4, respectively. When counter mark 22 on the upstream-end side ofcapsule body 2 is aligned with counter mark 22 on the downstream-endside of cap 3, upstream and downstream intake passages 7 and 8 of airintake path 6 are communicated with each other. When counter mark 22 onthe downstream-end side of capsule body 2 is aligned with counter mark22 on the upstream-end side of suction body 4, discharge passage 10 andconnecting passage 11 of air-powder mixture path 9 are communicated witheach other.

An operation of the thus-constructed inhalator of the present inventionwill be explained hereinafter.

When the inhalator is in a rest or nonuse position shown in FIG. 2,upstream and downstream intake passages 7 and 8 of air intake path 6 arefluidly disconnected from each other and discharge passage 10 andconnecting passage 11 of air-powder mixture path 9 are fluidlydisconnected from each other. In this state, powder receiving chamber 5is prevented from being fluidly communicated with the outside ofinhalator body 1 and air-powder mixture reservoir 12. Thus, if theinhalator is in the rest position, the powder received within powderreceiving chamber 5 can be restrained from flowing therefrom andinhalator body 1 when the user carries the inhalator.

Next, upon using the inhalator, cap 3 and suction body 4 are rotatedrelative to capsule body 2 to align respective counter marks 22 witheach other. Regulator 21 is axially moved in grooved portion 4B so as todesirably adjust the opening area of second diluent air passage 20. Theinhalator is thus placed in a use position shown in FIG. 6. In the useposition, upstream and downstream intake passages 7 and 8 of air intakepath 6 are fluidly connected with each other and discharge passage 10and connecting passage 11 of air-powder mixture path 9 are fluidlyconnected with each other. Powder receiving chamber 5 is allowed to bein fluid communication with the outside of inhalator body 1 andair-powder mixture reservoir 12. In this state, air-powder mixtureoutlet 18 of inhalator body 1 is put into the user's oral cavity and theambient air is sucked by the user. The air is introduced into air intakepath 6 through air intake inlet 7A. The air then flows into powderreceiving chamber 5 as indicated by arrows in FIG. 6. The introduced airis admixed with the dose of the powder within powder receiving chamber5, forming the air-powder mixture. The air-powder mixture flows intofirst air-powder mixture reservoir 12 via discharge passage 10 andconnecting passage 11 of air-powder mixture path 9. The air-powdermixture is temporarily stored within air-powder mixture reservoir 12 andadmixed with the diluent air introduced through diluent air passage 19.The thus diluted air-powder mixture has a decreased flow rate flowinginto communication passage 13, and a reduced mixing ratio of the powderin the diluted air-powder mixture to the air in the diluted air-powdermixture.

The diluted air-powder mixture within first air-powder mixture reservoir12 flows into second air-powder mixture reservoir 14 via communicationpassage 13 and then enters into dispersion chamber 17 via dispersionpassages 16. There occurs a swirl flow of the diluted air-powder mixturewithin dispersion chamber 17. The swirl flow atomizes an aggregated massof the powder which remains in dispersion chamber 17, to thereby assurethe air-powder mixture containing fine particles of the powder in asuitably dispersed state. The air-powder mixture within dispersionchamber 17 is diluted by the diluent air introduced thereinto throughsecond diluent air passage 20 and regulator holes 21A of regulator 21.The thus diluted air-powder mixture then is discharged from air-powdermixture outlet 18 into the user's oral cavity.

As be appreciated from the above explanation, the air-powder mixtureflowing from powder receiving chamber 5 is diluted within air-powdermixture reservoir 12 by the diluent air introduced into air-powdermixture reservoir 12 through diluent air passage 19. A flow rate of theair-powder mixture is reduced within air-powder mixture reservoir 12 bythe introduction of the diluent air. As a result, a part of the dose ofthe powder received within powder receiving chamber 5 is sucked byone-time inhalation by the user. Therefore, the dose of the powderreceived within powder receiving chamber 5 can be divided into aplurality of dose parts each being sucked by the user. Thus, the usercan suck a small amount of the powder that forms each dose part, byone-time inhalation. If it is required to deposit fine particulatemedicament having a small particle diameter in the bronchi or alveoli ofa patient, a dose of the medicament can be dispensed in parts which areinhaled by multiple-time inhalation of the user through the inhalator ofthe invention. The fine particulate medicament can be prevented frombeing deposited in the trachea and be stably deposited in the bronchi oralveoli by multiple-time inhalation of the dose parts. The inhalator ofthe invention can be effectively used for dispensing a dose of a powderor powder composition such as particulate medicament and powder tobacco,in parts by multiple-time inhalation.

Further, with the arrangement of second diluent air passage 20 andregulator 21 for regulating the opening area of diluent air passage 20,an amount of the diluent air introduced into dispersion chamber 17 canbe desirably regulated by axially moving regulator 21. A mixing ratiobetween the powder and the air present in the air-powder mixture withindispersion chamber 17 can be readily controlled by the regulation of thediluent air to be introduced. Accordingly, an amount of the powder whichis sucked by one-time inhalation by the user, can be desirablycontrolled using regulator 21 depending on the user's liking, kinds ofparticulate medicaments, or the like. This can improve a performance ofthe inhalator. The amount of the powder for one-time inhalation may becontrolled by regulating the opening area at the connection of upstreamand downstream intake passages 7 and 8 of air intake path 6 or theopening area at the connection of discharge passage 10 and connectingpassage 11 of air-powder mixture path 9.

Furthermore, with the arrangement of dispersion passages 16 anddispersion chamber 17 at dispersion part 15, the swirl flow of theair-powder mixture can be produced within dispersion chamber 17, whichatomizes an aggregated mass of the powder remaining in dispersionchamber 17 and forms the air-powder mixture containing the powderparticles in a good dispersed state. This can improve a dispersionefficiency of the inhalator.

Further, upstream and downstream intake passages 7 and 8 of air intakepath 6 is arranged to establish and block the fluid communicationbetween powder receiving chamber 5 and the outside of inhalator body 1.When the inhalator is in the nonuse position, upstream and downstreamintake passages 7 and 8 are disconnected from each other so that thefluid communication between powder receiving chamber 5 and the outsideof inhalator body 1 is blocked. In addition, discharge passage 10 andconnecting passage 11 of air-powder mixture path 9 is arranged to allowand block the fluid communication between powder receiving chamber 5 andfirst air-powder mixture reservoir 12. In the nonuse position of theinhalator, discharge passage 10 and connecting passage 11 aredisconnected from each other so that the fluid communication betweenpowder receiving chamber 5 and first air-powder mixture reservoir 12 isblocked. With this arrangement of intake passages 7 and 8 and dischargepassage 10 and connecting passage 11, the powder received within powderreceiving chamber 5 can be prevented from flowing therefrom toward bothair intake inlet 7A and air-powder mixture reservoir 12 upon the usercarrying the inhalator. This can improve reliability of the inhalator.Further, when intake passages 7 and 8 are communicated with each otherupon using the inhalator, the opening area of the connection of intakepassages 7 and 8 can be regulated to control the flow amount of the airflowing into powder receiving chamber 5. Therefore, the amount of thepowder present in the air-powder mixture produced within powderreceiving chamber 5 can be adjusted. Similarly, upon communication ofdischarge passage 10 and connecting passage 11, the opening area of theconnection thereof can be regulated to control the flow amount of theair-powder mixture flowing from powder receiving chamber 5 intoair-powder mixture reservoir 12. The amount of the powder in theair-powder mixture flowing from air-powder mixture reservoir 12 towardair-powder mixture outlet 18 can be adjusted, and therefore, the amountof the powder to be sucked can be adjusted.

Although two air-powder mixture reservoirs 12 and 14 are provided withinsuction body 4 in this embodiment, a single air-powder mixture reservoiror three or more air-powder mixture reservoirs may be provided.

In addition, a capsule chamber for storing a capsule having a dose ofthe powder may be substituted for powder receiving chamber 5. In thiscase, the capsule within the capsule chamber may be pierced using apiercing device upon inhalation.

Further, a shutter member may be provided for blocking and allowing thefluid communication between powder receiving chamber 5 and the outsideof inhalator body 1 and air-powder mixture reservoir 12, instead of thearrangement of upstream and downstream intake passages 7 and 8 of airintake path 6 and discharge passage 10 and connecting passage 11 ofair-powder mixture path 9. The shutter member may be rotatably orslidably disposed within air intake path 6 extending between powderreceiving chamber 5 and air intake inlet 7A and the portion ofair-powder mixture path 9 which extends between powder receiving chamber5 and air-powder mixture reservoir 12.

Furthermore, either one of the upstream end portion of capsule body 2and engaging tube portion 3A of cap 3 may have on the outercircumferential surface a groove circumferentially extending within apredetermined angular region. The other may have on the outercircumferential surface a projection engageable with the groove suchthat both capsule body 2 and cap 3 are rotatably moveable to each otherin the predetermined angular region. A similar circumferentiallyextending groove may be formed on either one of the outercircumferential surface of the downstream end portion of capsule body 2and the outer circumferential surface of engaging tube portion 4A ofsuction body 4, and a similar projection may be formed on the otherthereof. If the projections reach the respective ends of the grooves,the communication between upstream and downstream intake passages 7 and8 and the communication between discharge passage 10 and connectingpassage 11 will be established. In this case, counter marks 22 can beomitted.

Next, a powder composition for use with inhalators and a process foradministering the powder composition using inhalators, according to thepresent invention, will be explained hereinafter.

The powder composition is suitable to be administered from an oral ornasal cavity for deposition in inside parts of the human body. Thepowder composition includes at least two kinds of fine particlesselected from a group consisting of a first kind of fine particle havingan aerodynamic mean particle diameter of not less than 7 μm, a secondkind of fine particle having an aerodynamic mean particle diameter of5-7 μm, a third kind of fine particle having an aerodynamic meanparticle diameter of 3-5 μm, a fourth kind of fine particle having anaerodynamic mean particle diameter of 1-3 μm, and a fifth kind of fineparticle having an aerodynamic mean particle diameter of not more than 1μm. The first kind of fine particle having the aerodynamic mean particlediameter of not less than 7 μm is deposited in an oral cavity orhypoglottis of a human body. The second kind of fine particle having theaerodynamic mean particle diameter of 5-7 μm is deposited in a throat ofa human body. The third kind of fine particle having the aerodynamicmean particle diameter of 3-5 μm is deposited in a trachea of a humanbody. The fourth kind of fine particle having the aerodynamic meanparticle diameter of 1-3 μm is deposited in bronchi of a human body. Thefifth kind of fine particle having the aerodynamic mean particlediameter of not more than 1 μm is deposited in alveoli of a human body.

Preferably, the fine particles of the powder composition of the presentinvention have a significantly narrow particle size distribution. Morepreferably, the fine particles have the particle size distributionconsistent with a predetermined range of an aerodynamic mean particlediameter which is required for deposition in the respective parts of thehuman body.

The powder composition may be powder tobacco and particulate medicament.The powder tobacco contains at least two kinds of fine particlesselected from the first, third and fifth kinds of fine particles asdescribed above. For instance, the powder tobacco may contain fineparticles as a gustatory component which have the aerodynamic meanparticle diameter of 45-55 μm for deposition in the oral cavity orhypoglottis, fine particles as a stimulatory component which have theaerodynamic mean particle diameter of 3-5 μm for deposition in thetrachea or throat, and fine particles as an agent which have theaerodynamic mean particle diameter of 0.5-2 μm for deposition in thealveoli or bronchi. A coffee extract powder may be used for the fineparticles as a gustatory component having the aerodynamic mean particlediameter of 45-55 μm. A menthol extract powder may be used for the fineparticles as a stimulatory component having the aerodynamic meanparticle diameter of 3-5 μm. A nicotine extract powder may be used forthe fine particles as an agent having the aerodynamic mean particlediameter of 0.5-2 μm. If the powder tobacco is inhaled with theinhalator, the same taste, stimulus and nicotinic effect as thoseobtained by smoking can be obtained.

The particulate medicament as the powder composition of the presentinvention contains at least two kinds of fine particles selected fromthe first through fifth kinds of fine particles as described above. Theparticulate medicament may contain fine particles as a gustatorycomponent which have the aerodynamic mean particle diameter of 60-80 μmfor deposition in the oral cavity or hypoglottis, fine particles as anantiphlogistic agent which have the aerodynamic mean particle diameterof 4-6 μm for deposition in the trachea or throat, and fine particles asan agent which have the aerodynamic mean particle diameter of 1-3 μm fordeposition in the alveoli or bronchi. A powdered troche or candy may beused for the fine particles as a gustatory component having theaerodynamic mean particle diameter of 60-80 μm. An antiphlogistic powdermay be used for the fine particles as an antiphlogistic agent having theaerodynamic mean particle diameter of 4-6 μm. An antibiotic powder maybe used for the fine particles as an agent having the aerodynamic meanparticle diameter of 1-3 μm.

In addition, the particulate medicament as the powder composition of thepresent invention may be selected from an analgesic agent, an anginalpreparation, an antiallergic agent, an anti-infective agent, anantihistaminic agent, an anti-inflammatory agent, an antitussive agent,a bronchodilator agent, a diuretic agent, an anticholinergic agent, andthe like, depending on cure purposes. These powder agents may havevarious aerodynamic mean particle diameters suitable for deposition indifferent target parts of the human body.

If required, the particulate medicament as the powder composition of thepresent invention may be used together with a known excipient acceptablefor inhalation into the human body. The composition of the particulatemedicament is prepared in accordance with the doctor's prescriptiongiven on the basis of the patient's symptom.

In the administration process of the present invention, first the powdercomposition is prepared so as to contain at least two kinds of fineparticles selected from the first to fifth kinds of fine particles asdescribed above. The at least two kinds of fine particles of the powdercomposition may be blended together. The thus prepared powdercomposition is supplied to an inhalator suitable for dispensing a powderinto the human body. The powder composition may be capsulated and thenaccommodated in the inhalator. Subsequently, the powder compositionsupplied is discharged from the inhalator. If the above-describedinhalator of the present invention is used, the powder composition maybe dispersed within the inhalator and then discharged therefrom withoutaggregation of the fine particles of the powder composition.

The powder composition and administration process of the presentinvention can be suitably used for cure of multiple diseases using theparticulate medicaments which have effects on the multiple diseases,respectively. Specially, the powder composition and administrationprocess of the present invention is suitable for providing analgesia andcuring inflammation in the oral cavity and/or throat, asthma,bronchitis, COPD (chronic obstructive pulmonary disease), respiratorydisease such as thoracho-infection, and allergosis.

The inhalators useable in this embodiment are described in JapanesePatent Applications First Publication Nos. 62-41668 and 9-47509,Japanese Patent Application Second Publication No. 63-6024, and U.S.Pat. No. 5,996,577.

EXAMPLES

The present invention is described in more detail by way of examples.However, these examples are only illustrative and not intended to limita scope of the present invention thereto.

Example 1

A dose of a powder tobacco was prepared by blending 5 mg of coffeeextract particulates having an aerodynamic mean particle diameter of 50μm, 10 mg of menthol extract particulates having an aerodynamic meanparticle diameter of 4 μm, and 1 mg of nicotine extract particulateshaving an aerodynamic mean particle diameter of 0.5-2 μm together. Thethus prepared dose of a powder tobacco was supplied to a suitableinhalator as described above and then discharged from the inhalator.

Example 2

A dose of a particulate medicament mixture was prepared by blendingcandy particles having an aerodynamic mean particle diameter of 70 μm,antiphlogistic agent particles having an aerodynamic mean particlediameter of 5 μm, antibiotic agent particles having an aerodynamic meanparticle diameter of 2 μm together in accordance with a doctor'sprescription. The thus prepared dose of a particulate medicament mixturewas filled in a capsule. The thus capsulated dose of a particulatemedicament mixture was accommodated in a suitable inhalator as describedabove and then discharged from the inhalator.

Using the powder composition and the administration process of thepresent invention, a dose of the powder composition containing the atleast two kinds of fine particulates different in mean particle diameterfrom each other can be selected depending on the target parts of thehuman body in which the powder composition is required to be deposited,and can be deposited in the target parts by one-time inhalation usingthe inhalator. Namely, multi-purpose dosage of particulate medicaments,for instance, deposition of the particulate medicaments in both of thetrachea and the alveoli or all of the throat, the bronchi and thealveoli, can be achieved during the one-time inhalation.

Further, using the powder composition and the administration process ofthe present invention, the patient can dispense with multiple times ofinhalation for dosing a plurality of particulate medicaments required indifferent prescriptions. Also, any specific compound of particulatemedicaments may not be required for multi-purpose prescription.

Furthermore, in a case where the capsulated powder composition ofparticulate medicaments having different mean particle diameters isused, the patient can dispense with adjusting the amount of the powdercomposition required for each inhalation and the mixing ratio of thedifferent kinds of particulate medicaments.

The entire contents of basic Japanese Patent Applications Nos.2000-363636 filed on Nov. 29, 2000, and 2000-359822 filed on Nov. 27,2000, inclusive of the specification, claims and drawings, are hereinincorporated by reference.

Although the invention has been described above by reference to certainembodiments of the invention, the invention is not limited to theembodiments described above. Modifications and variations of theembodiment described above will occur to those skilled in the art, inlight of the above teachings. The scope of the invention is defined withreference to the following claims.

What is claimed is:
 1. An inhalator for administering an air-powdermixture, comprising: an inhalator body including an air intake path forintroducing an air into the inhalator body, and an air-powder mixtureoutlet for discharging the air-powder mixture from the inhalator body; apowder receiving chamber adapted to receive a powder, the powderreceiving chamber being disposed within the inhalator body andcommunicated with an outside of the inhalator body through the airintake path; an air-powder mixture path adapted to transmit theair-powder mixture flowing from the powder receiving chamber to theair-powder mixture outlet; an air-powder mixture reservoir adapted totemporarily store the air-powder mixture flowing from the powderreceiving chamber, the air-powder mixture reservoir being disposedwithin the air-powder mixture path; a diluent air passage adapted tointroduce a diluent air into the air-powder mixture reservoir, thediluent air passage communicating the air-powder mixture reservoir withthe outside of the inhalator body; and a second diluent air passageadapted to introduce a diluent air into the air-powder mixture pathdownstream of the air-powder mixture reservoir upon the air-powdermixture flowing from the air-powder mixture reservoir, and a regulatorvariably controlling an opening area of the second diluent air passage.2. An inhalator for administering an air-powder mixture, comprising: aninhalator body including an air intake path for introducing an air intothe inhalator body, and an air-powder mixture outlet for discharging theair-powder mixture from the inhalator body; a powder receiving chamberadapted to receive a powder, the powder receiving chamber being disposedwithin the inhalator body and communicated with an outside of theinhalator body through the air intake path; an air-powder mixture pathadapted to transmit the air-powder mixture flowing from the powderreceiving chamber to the air-powder mixture outlet; an air-powdermixture reservoir adapted to temporarily store the air-powder mixtureflowing from the powder receiving chamber, the air-powder mixturereservoir being disposed within the air-powder mixture path; a diluentair passage adapted to introduce a diluent air into the air-powdermixture reservoir, the diluent air passage communicating the air-powdermixture reservoir with the outside of the inhalator body; and adispersion part adapted to disperse the powder in the air-powder mixturepassing through the air-powder mixture path downstream of the air-powdermixture reservoir, wherein the dispersion part comprises a plurality ofdispersion passages branched from the air-powder mixture path downstreamof the air-powder mixture reservoir, and a dispersion chamber disposedwithin the air-powder mixture path downstream of the dispersionpassages, each of the dispersion passages having an outlet passageportion that is open into the dispersion chamber and arranged to form aswirl flow of the air-powder mixture.
 3. The inhalator as claimed inclaim 2, wherein the dispersion chamber has a generally circular-shapedsection and the outlet passage portion of each of the dispersionpassages extends in a tangential direction of the dispersion chamber. 4.An inhalator for administering an air-powder mixture, comprising: aninhalator body including an air intake path for introducing an air intothe inhalator body, and an air-powder mixture outlet for discharging theair-powder mixture from the inhalator body; a powder receiving chamberadapted to receive a powder, the powder receiving chamber being disposedwithin the inhalator body and communicated with an outside of theinhalator body through the air intake path; an air-powder mixture pathadapted to transmit the air-powder mixture flowing from the powderreceiving chamber to the air-powder mixture outlet; an air-powdermixture reservoir adapted to temporarily store the air-powder mixtureflowing from the powder receiving chamber, the air-powder mixturereservoir being disposed within the air-powder mixture path; and adiluent air passage adapted to introduce a diluent air into theair-powder mixture reservoir, the diluent air passage communicating theair-powder mixture reservoir with the outside of the inhalator body,wherein the air intake path is arranged to allow and block fluidcommunication between the powder receiving chamber and the outside ofthe inhalator body, and wherein the air intake path comprises at leasttwo passages having an alignment position where the at least twopassages are in alignment with each other and an offset position wherethe at least two passages are out of alignment with each other.
 5. Aninhalator for administering an air-powder mixture, comprising: aninhalator body including an air intake path for introducing an air intothe inhalator body, and an air-powder mixture outlet for discharging theair-powder mixture from the inhalator body; a powder receiving chamberadapted to receive a powder, the powder receiving chamber being disposedwithin the inhalator body and communicated with an outside of theinhalator body through the air intake path; an air-powder mixture pathadapted to transmit the air-powder mixture flowing from the powderreceiving chamber to the air-powder mixture outlet; an air-powdermixture reservoir adapted to temporarily store the air-powder mixtureflowing from the powder receiving chamber, the air-powder mixturereservoir being disposed within the air-powder mixture path; and adiluent air passage adapted to introduce a diluent air into theair-powder mixture reservoir, the diluent air passage communicating theair-powder mixture reservoir with the outside of the inhalator body,wherein the air-powder mixture path is arranged to allow and block fluidcommunication between the powder receiving chamber and the air-powdermixture reservoir, and wherein the air-powder mixture path comprises atleast two passages disposed between the powder receiving chamber and theair-powder mixture reservoir, the plurality of passages having analignment position where the at least two passages are aligned with eachother and an offset position where the at least two passages are offsetfrom each other.
 6. The inhalator as claimed in claim 2, furthercomprising a second air-powder mixture adapted to temporarily store theair-powder mixture flowing from the first air-powder mixture reservoirtoward the dispersion passages of the dispersion part.
 7. The inhalatoras claimed in claim 6, wherein each of the dispersion passages comprisesan inlet open into the second air-powder mixture reservoir.
 8. Aninhalator for administering an air-powder mixture, comprising: a casingincluding an air intake inlet for introducing an air into the casing,and an air-powder mixture outlet for discharging the air-powder mixturefrom the casing; powder receiving means for receiving a powder withinthe casing and permitting the powder to be admixed with the airintroduced from the air intake inlet; air-powder mixture storing meansfor temporarily storing the air-powder mixture passing through thepowder receiving means; diluent air passage means for permitting adiluent air to flow into the air-powder mixture storing means;air-powder mixture path means for permitting the air-powder mixture toflow from the powder receiving means to the air-powder mixture outletvia the air-powder mixture storing means; and a second diluent airpassage means for permitting a diluent air to flow into the air-powdermixture path means downstream of the air-powder mixture storing meansupon the air-powder mixture flowing from the air-powder mixture storingmeans.
 9. The inhalator as claimed in claim 8, further comprising aregulator variable controlling an opening area of the second diluent airpassage means.
 10. The inhalator as claimed in claim 8, furthercomprising air intake path means for permitting the air to flow from theair intake inlet into the powder receiving means.
 11. The inhalator asclaimed in claim 8, wherein the air-powder mixture path means allows andblocks fluid communication between the powder receiving means and theair-powder mixture storing means.
 12. An inhalator for administering anair-powder mixture, comprising: a casing including an air intake inletfor introducing an air into the casing, and an air-powder mixture outletfor discharging the air-powder mixture from the casing; powder receivingmeans for receiving a powder within the casing and permitting the powderto be admixed with the air introduced from the air intake inlet;air-powder mixture storing means for temporarily storing the air-powdermixture passing through the powder receiving means; diluent air passagemeans for permitting a diluent air to flow into the air-powder mixturestoring means; air-powder mixture path means for permitting theair-powder mixture to flow from the powder receiving means to theair-powder mixture outlet via the air-powder mixture storing means; anddispersion means for preventing the powder in the air-powder mixturefrom being aggregated together, wherein the dispersion means comprisespassages means for forming a swirl flow of the air-powder mixture andchamber means for receiving the swirl flow of the air-powder mixture.13. The inhalator as claimed in claim 12, wherein the chamber means hasa generally circular-shaped section and the passage means extends in atangential direction of the chamber means.
 14. The inhalator as claimedin claim 12, further comprising air intake path means for permitting theair to flow from the air intake inlet into the powder receiving means.15. The inhalator as claimed in claim 12, wherein the air-powder mixturepath means allows and blocks fluid communication between the powderreceiving means and the air-powder mixture storing means.